This invention relates to fluid-gauging systems and methods.
Aircraft fuel tanks usually have several probes disposed to measure the height of fuel within the tank at different locations. The probes may be of any conventional kind, such as capacitive or ultrasonic probes. The probes are preferably located in a non-linear fashion, that is so that the locations of no three probes lie on a straight line. In this way, the maximum information can be obtained about the orientation of the surface plane of the fuel. In practice, however, it is not usually possible to locate all probes within a tank so that no three are arranged in a straight line or an almost straight line because of limited availability of fixing points, intrusions into the tank and other factors. The construction of fuel-gauging probes can make them prone to false readings if, for example, there is a blockage of fuel flow into or out of the probe, an accumulation of foam within the probe, adverse thermal stratification conditions, water contamination, damage to the probe or the like. Because of the movement of the fuel surface within the tank, it is not always immediately apparent when a probe is providing a false height reading.